1. Field of the Invention
This invention relates generally to transducer suspension systems and more particularly to a suspension system having reinforcing stamped recesses.
2. Description of the Prior Art
Direct access storage devices (DASD), otherwise known as disk drives, store information on concentric tracks of a rotatable magnetic recording disk. A magnetic head or transducer element is moved from track to track to record and read the desired information. Typically, the magnetic head is positioned on an air bearing slider which flies above the surface of the disk as the disk rotates. In some recently proposed disk drives, the slider (or carrier) rides on a liquid film or bearing on the disk. A suspension assembly connects the slider to a rotary or linear actuator. The suspension provides support for the slider.
The suspension must meet several requirements. It must have a gimbal assembly in order to allow the slider to pitch and roll as it adjusts to the air bearing created between the slider and the rotating disk. The suspension must also have a flexible spring section to provide a bias force in the vertical direction. This is necessary to provide a compensating force to the lifting force of the air bearing in order to keep the slider at the desired height above the disk. Also, the suspension must have a rigid load beam section between the gimbal assembly and the spring section in order to prevent unwanted displacement.
Examples of suspension systems are shown in U.S. Pat. No. 5,408,372 issued Apr. 18, 1995 to Karam; U.S. Pat. No. 5,313,355 issued May 17, 1994 to Hagen; U.S. Pat. No. 5,313,353 issued May 17, 1994 to Kohso et al; U.S. Pat. No. 5,126,904 issued Jun. 30, 1992 to Sakurai; U.S. Pat. No. 4,996,616 issued Feb. 26, 1991 to Aoyagi et al; U.S. Pat. No. 4,167,765 issued Sep. 11, 1979 to Watrous; Japanese Patent Application 4-313870 published Nov. 5, 1992 by Mori; Japanese Patent Application 3-219473 published Sep. 26, 1991 by Kuwamoto; Japanese Patent Application 60-226080 published Nov. 11, 1995 by Okuwaki; Japanese Patent Application 60-025073 publish Feb. 7, 1995 by Masanobu; IBM Technical Disclosure Bulletin Vol. 36, No. 4, April 1993, page 71 by Satoh et al; and NHK NP30 product specification sheet dated Sep. 27, 1993.
In the past, each disk drive maker has had to design their own suspension for their own drives. Each type of drive tended to use its own special suspension design. One reason for this is that if the length of the suspension is varied, then the dynamic characteristics of the suspension also change. This resulted in the need to redesign each suspension for every change in suspension length. Another related problem is that the past designs tended to have a relatively large and thick actuator arm which projected towards the disk and to which the suspension was attached. In order to obtain desirable frequency response characteristics in the suspension, the actuator arm was extended as far as possible towards the disk. However, this large actuator arm contributes to the mass of the actuator which in turn slows the actuator""s speed and results in relatively slower data access times.
What is needed is a suspension design which provides for a variable length suspension and which reduces the length of the actuator arm.
Briefly, in a preferred embodiment of the present invention, a suspension system comprises a first rigid beam section having a first portion for connection to an actuator arm. The first rigid beam section has at least one stamped ridge which extends over the actuator arm and along the length of the first rigid section. A flexible spring section is connected to the first rigid section. A second rigid section is connected to the spring section and has a transducer assembly receiving portion for receiving a transducer assembly.
The stamped ridge provides great stiffness to the first rigid section and in effect extends the stiffness of the actuator arm out through the first rigid section to the beginning to the spring section. Thus, the actuator arm does not need to extend as far. The spring section and the second rigid section may be of a standard length such that the overall length of the suspension may be varied by simply changing the length of the first rigid section without substantially changing the dynamic characteristics of the suspension.
For a fuller understanding of the nature and advantages of the present invention, reference should be made to the following detailed description taken in conjunction with the accompanying drawings.